This is a circa 1925 Rapid Calculator Co. pinwheel adding machine. A description from the National Museum of American History states; \"This pinwheel calculating machine has nine levers for setting numbers, ten wheels for recording numbers of revolutions of the large drum, and 18 wheels for recording results. The large handle for operating the machine is on the right at the top. The carriage has two zeroing handles. Lifting a movable bar zeros the levers. Depressing a knob at the front releases the carriage.\" Includes original cover that is dented and letters worn. The calculator measures 14 3/4\" long, 6\" tall and 7\" deep.

---